In a device of this type, it is known to guide the pushing and pulling element in a coaxial bore in the piston rod, the rod-like end region of the pushing and pulling element protruding through the interior of the cylinder. This design requires seals both on the pushing and pulling element, which is guided from the outside into the interior of the cylinder, and on the piston rod, which is guided to the outside, the seal of the pushing and pulling element being arranged on an axially movable component and therefore provides an increased leakage problem.